Studies are being made on levels of skin calcium and phosphate in and rates of uptake of calcium and phosphate from buffered solutions by skin punch biopsies from patients with pseudoxamthoma elasticum (PXE) and from normal controls. Fibroblast cultures are being grown from these biopsies. Polyanions and other macromolecules are being extracted from PXE skin and from the fibroblast cultures with the object of defining any abnormal calcium binding substances related to the elastic fiber calcification characteristic of PXE. Methods of measurement and the course of development of the characteristic skin, retinal and vascular lesions are being studied as well as methods of arresting the progress of these lesions by treatment. Information is being sought of involvement of other organs such as brain and lung, and elastic tissue from other tissues than skin, eye and artery.